<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        let arr = [1, 'aa', null, undefined, 'obj'];
         // let [a, b, c, d, f] = arr;
          // console.log(a, b, c, d, f); 
          let [, , a] = arr;
           console.log(a)
    </script>
</body>
</html>